Method and apparatus for making finned tubes



Dec. 8, 1953 R. c. EDWARDS 2,661,525

METHOD AND APPARATUS FOR MAKING FINNED TUBES Filed Aug. 8, 1949 2 Sheets-Sheet l INVENTOR.

Dec. 8, 1953 R. c. EDWARDS 2,661,525

METHOD AND APPARATUS FOR MAKING FINNED TUBES Filed Aug. 8, 1949 2 Sheets-Sheet 2 mm hull IN V EN TOR.

Patented Dec. 8, 1953 METHOEAND urARa'rusronMAKme FINNED runes Ray C: Edwards, GlenRock, NJ. I

Applicattonmrmtw,1949;.Scrial-:No.109,085;

8 claims (01. 292-15713) The invention herein disclosed relates to; ma.- chines for making radiator, condenser, or. com vector tubes which have extended surfacesmade up of a strip or ribbon of thin material, preferably sheet metal wound spirally around the tube. The primary object isto-provide-a machinewhich is compact in formand into which. a tube is fed and rotated in such a manner that a plurality of thin-strips of material, preterrabl-y metal, may be helically wound around. the tube and secured thereon all in one operation. Prior to this: time ithad been customary to apply only one thin strip of ribbon at onetime.

By helically wrapping twoor more fms simulttaneously about the tube a nm'nber of" important objectives and. advantages are realized:

First, the production rate of the framing. ma.- chine' is increased in proportion: to the number at finsapplied simultaneously.

Secondly, an equally important object of this machine is to' include a slitting device as part: of

the machine mechanism. With a means. for slitthis it is possible to utilize low cost wide fin strip and slit the strip as it is fed into the machine. 5

Narrow finned strip is costly.

Thirdly, by slitting the strip as it is fed to the finning machine the diiiiculties encountered handling a narrow thin strip are eliminated.

In the drawings:

Figure 1 is an isometric view of the complete slitting, crimping, finning and synchronizing mechanism.

Figure 2 is a side view of the slitting rollers.

Figure 3 is a top view of the slitting rollers.

Figure 4 is a side view of the finned tube.

Figure 5 is an end view of the finned tube.

Figure 6 is a side elevation of the machanism used to apply the fin strip to the tube.

Figure 7 is a top view of the mechanism used to apply the fin strip to the tube.

On Figure 1 of the drawing, I illustrates the Wide initial strip, preferrably of metal, from which the fins are formed. It was found advisable to purchase the strip in widths greater than A,". Strips with widths greater than A" may be purchased for as much as less per pound than narrower strips. Also, most suppliers are very reluctant to take the responsibility of slitting and reeling the narrow strips. For the con densation of refrigerant vapors, particularly the organic refrigerants, fins Mi" wide are preferred However, the purchase of such narrow strip is im practical, as the strips snarl Severely when wound on reels in preparation for shipment.

The strip l pa s etween the slitting rollers 2 driyen by. a belt. drive. Power for driving the slitting rollers isobtained directly from the trans; mission 3 or from the; shaft driving the crimping gears 4.v The. slitting rollers 2 are of conventional. design and basically consist of hardened steelground discs having. a. thickness correspond,- ing-gto the. Width. of the slit strip. The slitting rolilers, are of two, diameters. and are alternated on their driving shafts so. that they will mesh. and slit the strip. as it passes. between them.

Aiter slitting, the component strands pass around a pin 5.. The. pin divides the strip. into the number of strands into which they strip. has

been. slit and the. pin. 1 assures that. the, strip has been separated into. its. component strands...

After the components. Strips pass, pin 5. the strands pass around. idler pulley 6. and thence'to the crimping mechanism. The purpose of idler pulley 6. isto tension thestrands after they leave the slitter, and. also to synchronize the op r tion of the crim-pcr and slitter. If. the strands of stripping lea-re the slitter more rapidly. than they pass throughthe crimper l idler pulley 6 drops and by means of synchronizing link 5, the slitting operation is retarded, until the slitting and crimping take place, at a simultaneous rate. or until the two operationsv are synchronized,

The. synchronizing is accomplished by the following. procedure;

If the slitting rollers feed the slit strip too rapidly, idler pulley 6 drops, this in turn raises idler pulley I. When idler pulley I raises, the belt 9 moves outward radially on the spring loaded synchronizing pulley 8, thereby increasing the operating diameter of synchronizing pul-. ley 8. When. theo-perating diameter of 8. in,- creases, the rotative speed of the slitting cutters, which are mounted on the. same shaft as the synchronizi-ng pulley.8,--is slowed down with respect to the shaft l0. upon which the crimp n gears! are mounted. V The opposite sequence of events occurs if idler pulley 6 is caused to rise. In that. event the. slit, ting cutters are driven more rapidly with respect to the crimping gears.

In some instances itmight. not be desirable to employ the use of crimping gears. In that case the plurality of-strips can be fed directly to the, tube and simultaneously Wound on thetube with out the crimp. Also, if the crimping operation eliminated, the slitting cutters could be driven by the transmission 3 rather than by the shaft 4. upon which one of the crimping gears is After passing over idler pulley I l, the slit strips pass into the crimper 4 Within the crimper the r not shown and are located in the transmission.-

The operation of the crimping mechanism is synchronized with the rotation of the tube by the same type of mechanism used to synchronize the slitting and the crimping operation. Y An excess of crimped strip will lower the posi- .tion of idler H, which in turn'raises the position of idler I9, which causes the spring loaded synchronizing pulley 20 to increase its effective pitch diameter. Increasing the pitch diameter of synchronizing pulley 20 slows the operation of this pulley down with respect to the rotation of speed of the transmission 3, and thus correspondingly the crimping gears which are mounted on the same shaft. If idler pulley I 2 is caused to rise for any reason the opposite sequence of events will occur. As the tube IS in its rotational and translational motion leaves the ironing roller 16 the finned tube is then subjected to a spray I! of soldering flux. After leaving the flux spray the tube transversely movesinto a spray of molten solder I8 and there the applied fin of the multiple pitch is bonded to the tube.

All of the operations herein described operate simultaneously and no other care is required by the operator than the replacement of strip and tube as it is used by the machine.

What I claim is the following:

1 The method of applying thin narrow radiation fins on a tube, which consists in splitting a relatively wide strip of thin metal into a plurality of uniform narrow strips, passing the thin narrow strips simultaneously through crimping means for laterally crimping them, simultaneously winding the thin narrow strips in uniform spaced parallel relation edgewise upon a tube, applying soldering flux to the strips wound upon the tube, subjecting the tube and strips to a soldering bath for coating and securing the strips to the tube, and synchronizing the feeding of the wide strip during the splitting operation with the crimping and winding operations of the nar-: row strips.

2. The method of applying thin narrow fins strips in approximate edgewise alignment during the crimping operation, guiding the narrow Strips into parallel relationship and simultaneously winding the parallel narrow strips edgewise in uniform spaced relation upon a tube, applying soldering flux to the strips wound upon the tube,- subjecting the tube and strips to a soldering bath-' for coating and securing the strips to the tube,- and synchronizing the feeding of the wide stripduringthe splitting operation with the crimping and winding operations of the narrow strips.

. 4. The method of applying thin narrow fins on a tube which consists in continuously moving a fin-forming metal strip from a source of supply until the fins are applied to a tube and during said continuous movement splitting the metal strip into a plurality of uniform narrow strips [in approximately edgewise alignment, guiding the narrow strips from edgewise alignment into paron a tube which consistsin continuously moving afin forming metal strip froma source of supply until the fins are applied to a tube and during said continuous movement splitting the metal strip into a plurality of uniform narrow strips, simultaneously crimping the narrow strips laterally of their length, maintaining the narrow strips in approximate edgewise alignment during the crimping operation, guiding the narrow strips into parallel relationship and simultaneously winding the parallel narrow strips edgewise in uniform spaced relation upon a tube. e

' 3. The method of applying thin narrow 'fins on a tube which consists in continuously moving a fin-forming metal strip from a source of supply until the fins are applied to a tube and during said continuous movement splitting the metal strip into a plurality of uniform narrow strips, simultaneously crimping the narrow strips jlaterally of their length, maintaining the B IE'QW allel relationship, simultaneously winding the parallel narrow strips edgewise in uniform spaced relation edgewise upon a tube, applying soldering flux to the strips wound upon the tube, and subjecting the tube and strips to a soldering bath for coating and securing the strips to the tube.

5. In a machine for making finned tubes, the combination of, means for revolving and moving longitudinally a tube to be finned, slitting means for slitting a metallic strip into a plurality of individual fin-forming strips, crimping rollers for simultaneously crimping said strips, means for driving said crimping rollers, means connecting said crimping roller driving means to said tube revolving and moving means to provide synchronous operation of said crimping rollers and said tube revolving means, means for driving said slitting means, power transmission means connecting the driving means of said slitting means and the driving means of said crimping rollers to provide synchronized operation of the splitting means and crimping rollers, a strip guiding comb supported adjacent to said tube to be finned and receiving said strips from said crimping rollers, said comb acting to guide said fin-forming strips into spaced parallel relationship with each other, and an ironing roller mounted adjacent to said comb and tube and receiving the fin-forming strips from said comb to deform and wind the strips in parallel edgewise relation about and in contact with the tube, means for driving said ironing roller, and means to provide synchronized operation of said ironing roller driving means and said tube revolving means.

6: In a machine for making finned tubes, the combination of, means for revolving and moving longitudinally a tube to be finned, slitting means for slitting a metallic ribbon into a plurality of individual fin-forming strips, means for driving said slitting means, power transmission means connecting the driving means of said slitting means and said tube revolving and moving means to provide synchronous operation of the slitting means and the tube revolving and moving means. means for deforming and winding the fin-forming strips in uniform parallel edgewise relation about and in contact with the tube, means for driving said fin-forming strip deforming and winding means, and means to provide synchronized operation of said strip deforming and winding means and said tube revolving means.

- "7. In a machine for making finned tubes, the combination of, means for revolving and moving longitudinally a tube to be finned, slitting means for slitting a metallic ribbon into a plurality of individual fin-forming strips, means for driving said slitting means, power transmission means connecting the driving means of said slitting means and said tube revolving and moving means to provide synchronous operation or" the slitting means and the tube revolving and. moving means, a strip guiding comb supported adjacent to the tube to be finned and engaging said tube forming strips, an ironing roller mounted adjacent said comb and tube and receiving the fin-forming strips from said comb to deform and wind the strips in uniform parallel edgewise relation about and in contact with the tube, means for driving said ironing roller and means to provide synchronized operation or said ironing roller driving means and said tube revolving means.

8. In a machine for making finned tubes, the combination of, means for revolving and moving longitudinally a tube to be finned, slitting means for slitting a metallic ribbon into a plurality of individual fin-forming strips, crimping rollers for simultaneously crimping said strips, means for driving said crimping rollers, means connecting said crimping roller driving meansto said tube revolving and moving means to provide synchronous operation of said crimping rollers and said tube revolving and moving means, means for driving said slitting means, power transmission means connecting the driving means of said slitting means and the driving means of said crimping rollers to provide synchronized operation of the slitting means and crimping rollers, an ironing roller mounted adjacent to said tube for deforming and Winding the fill-forming strips in uniform parallel edgewise relation about and in contact with the tube, means for driving said ironing roller, and means to provide synchronous operation of said ironing roller driving means and said tube revolving means.

RAY C. EDWARDS.

References Gited in the file Of this patent UNITED STATES PATENTS Number Name Date 264,174 Lenox Sept. 12, 1882 1,639,568 Wade Oct. 30, 1928 1,914,477 Berg June 20, 1933 1,920,155 Fisher July 25, 1933 2,039,690 Trainer -1 May 5, 1936 2,087,723 McCord July 20, 1937 2,095,599 Gleason Oct. 12, 1937 2,152,437 Lear Mar. 28, 1939 2,213,703 I-Ienning Sept. 3, 1940 2,214,618 Kenyon Sept. 10, 1940 2,251,074 Sibley July 29, 1941 2,251,642 I'illev Aug. 5, 1941 2,363,224 Bronander Nov. 21, 1944 2,422,272 Viehweger June 17, 1947 2,553,142 McCreary May 15, 1951 

